diff --git a/.github/workflows/ci-clang-tidy.yml b/.github/workflows/ci-clang-tidy.yml
index 658d3090..a9147356 100644
--- a/.github/workflows/ci-clang-tidy.yml
+++ b/.github/workflows/ci-clang-tidy.yml
@@ -124,12 +124,13 @@ jobs:
           sed -i.backup '/^\[settings\]$/,/^\[/ s/^build_type=.*/build_type=${{ matrix.build_type }}/' ~/.conan2/profiles/default
           conan profile show -pr default
       - run: echo "std_format=$([ "${{ matrix.formatting }}" == "std::format" ] && echo "True" || echo "False")" >> $GITHUB_ENV
+      - run: echo "import_std=$([ "${{ matrix.config.cxx_modules }}" == "True" ] && [ "${{ matrix.config.contracts }}" == "none" ] && [ "${{ matrix.formatting }}" == "std::format" ] && echo "True" || echo "False")" >> $GITHUB_ENV
       - name: Run clang-tidy
         shell: bash
         run: |
           conan build . -b missing -c tools.cmake.cmaketoolchain:generator="Ninja Multi-Config" \
                         -c user.mp-units.build:all=True -c user.mp-units.analyze:clang-tidy=True -c tools.build:skip_test=True \
-                        '-o &:cxx_modules=${{ matrix.config.cxx_modules }}' -o '&:std_format=${{ env.std_format }}' -o '&:contracts=${{ matrix.contracts }}' ${{ matrix.config.conan-config }}
+                        '-o &:cxx_modules=${{ matrix.config.cxx_modules }}' -o '&:import_std=${{ env.import_std }}' -o '&:std_format=${{ env.std_format }}' -o '&:contracts=${{ matrix.contracts }}' ${{ matrix.config.conan-config }}
       - name: Clean Conan cache before backup
         shell: bash
         run: |
diff --git a/.github/workflows/ci-conan.yml b/.github/workflows/ci-conan.yml
index 93241774..58df0880 100644
--- a/.github/workflows/ci-conan.yml
+++ b/.github/workflows/ci-conan.yml
@@ -238,12 +238,13 @@ jobs:
           sed -i.backup '/^\[settings\]$/,/^\[/ s/^build_type=.*/build_type=${{ matrix.build_type }}/' ~/.conan2/profiles/default
           conan profile show -pr default
       - run: echo "std_format=$([ "${{ matrix.formatting }}" == "std::format" ] && echo "True" || echo "False")" >> $GITHUB_ENV
+      - run: echo "import_std=$([ "${{ matrix.config.cxx_modules }}" == "True" ] && [ "${{ matrix.config.contracts }}" == "none" ] && [ "${{ matrix.formatting }}" == "std::format" ] && echo "True" || echo "False")" >> $GITHUB_ENV
       - name: Create Conan package
         shell: bash
         run: |
           conan create . --user mpusz --channel ${CHANNEL} --lockfile-out=package.lock \
-                         -b mp-units/* -b missing -c tools.cmake.cmaketoolchain:generator="Ninja Multi-Config" \
-                         -c user.mp-units.build:all=True -o '&:cxx_modules=${{ matrix.config.cxx_modules }}' -o '&:std_format=${{ env.std_format }}' -o '&:contracts=${{ matrix.contracts }}' ${{ matrix.config.conan-config }}
+                         -b mp-units/* -b missing -c tools.cmake.cmaketoolchain:generator="Ninja Multi-Config" -c user.mp-units.build:all=True \
+                         -o '&:cxx_modules=${{ matrix.config.cxx_modules }}' -o '&:import_std=${{ env.import_std }}' -o '&:std_format=${{ env.std_format }}' -o '&:contracts=${{ matrix.contracts }}' ${{ matrix.config.conan-config }}
       - name: Obtain package reference
         id: get-package-ref
         shell: bash
diff --git a/.github/workflows/ci-test-package-cmake.yml b/.github/workflows/ci-test-package-cmake.yml
index 4b3cacec..df1cae9f 100644
--- a/.github/workflows/ci-test-package-cmake.yml
+++ b/.github/workflows/ci-test-package-cmake.yml
@@ -231,11 +231,12 @@ jobs:
           sed -i.backup '/^\[settings\]$/,/^\[/ s/^build_type=.*/build_type=${{ matrix.build_type }}/' ~/.conan2/profiles/default
           conan profile show -pr default
       - run: echo "std_format=$([ "${{ matrix.formatting }}" == "std::format" ] && echo "True" || echo "False")" >> $GITHUB_ENV
+      - run: echo "import_std=$([ "${{ matrix.config.cxx_modules }}" == "True" ] && [ "${{ matrix.config.contracts }}" == "none" ] && [ "${{ matrix.formatting }}" == "std::format" ] && echo "True" || echo "False")" >> $GITHUB_ENV
       - name: Install Conan dependencies
         shell: bash
         run: |
           conan install . -b missing -c tools.cmake.cmaketoolchain:generator="Ninja Multi-Config" -c user.mp-units.build:all=False \
-                          -o '&:cxx_modules=${{ matrix.config.cxx_modules }}' -o '&:std_format=${{ env.std_format }}' -o '&:contracts=${{ matrix.contracts }}'
+                          -o '&:cxx_modules=${{ matrix.config.cxx_modules }}' -o '&:import_std=${{ env.import_std }}' -o '&:std_format=${{ env.std_format }}' -o '&:contracts=${{ matrix.contracts }}'
       - name: Provide dependencies for the build
         shell: bash
         working-directory: src
diff --git a/conanfile.py b/conanfile.py
index 2979b31a..3a8fd5f5 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -30,7 +30,7 @@ from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain, cmake_layout
 from conan.tools.files import copy, load, rmdir
 from conan.tools.scm import Version
 
-required_conan_version = ">=2.0.0"
+required_conan_version = ">=2.0.15"
 
 
 class MPUnitsConan(ConanFile):
@@ -239,7 +239,7 @@ class MPUnitsConan(ConanFile):
                 raise ConanInvalidConfiguration(
                     "'contracts' should be set to 'none' to use `import std;`"
                 )
-            if not self.options.std_format:
+            if not self.options.get_safe("std_format", default=True):
                 raise ConanInvalidConfiguration(
                     "'std_format' should be enabled to use `import std;`"
                 )
@@ -252,7 +252,9 @@ class MPUnitsConan(ConanFile):
         tc.absolute_paths = True  # only needed for CMake CI
         if self._build_all:
             tc.cache_variables["CMAKE_EXPORT_COMPILE_COMMANDS"] = True
-            tc.cache_variables["CMAKE_VERIFY_INTERFACE_HEADER_SETS"] = True
+            tc.cache_variables[
+                "CMAKE_VERIFY_INTERFACE_HEADER_SETS"
+            ] = not self.options.import_std
             tc.cache_variables["MP_UNITS_DEV_BUILD_LA"] = not self._skip_la
             if self._run_clang_tidy:
                 tc.cache_variables["MP_UNITS_DEV_CLANG_TIDY"] = True
@@ -287,7 +289,8 @@ class MPUnitsConan(ConanFile):
         if self._build_all or self.options.cxx_modules:
             cmake.build()
         if self._build_all:
-            cmake.build(target="all_verify_interface_header_sets")
+            if not self.options.import_std:
+                cmake.build(target="all_verify_interface_header_sets")
             if can_run(self):
                 cmake.ctest(cli_args=["--output-on-failure"])
 
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 611bfcc7..ce9db06b 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -126,10 +126,10 @@ if(${projectPrefix}BUILD_CXX_MODULES)
 endif()
 
 if(${projectPrefix}BUILD_IMPORT_STD)
-    target_compile_definitions(mp-units-core PUBLIC ${projectPrefix}IMPORT_STD)
+    target_compile_definitions(mp-units-core ${${projectPrefix}TARGET_SCOPE} ${projectPrefix}IMPORT_STD)
     # https://github.com/llvm/llvm-project/issues/75057
     if(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19)
-        target_compile_options(mp-units-core PUBLIC "-Wno-deprecated-declarations")
+        target_compile_options(mp-units-core ${${projectPrefix}TARGET_SCOPE} "-Wno-deprecated-declarations")
     endif()
 endif()